Terrestrial Origin for Abundant Riverine Nanoscale Ice-Nucleating Particles.

Ice-nucleating particles (INPs) associated with fresh waters are a neglected, but integral component of the water cycle. Abundant INPs were identified from surface waters of both the Maumee River and Lake Erie with ice nucleus spectra spanning a temperature range from -3 to -15 °C. The majority of river INPs were submicron in size and attributed to biogenic macromolecules, inferred from the denaturation of ice-nucleation activity by heat.